T_（BB）资料揭示的亚澳季风区季节转换及亚洲夏季风建立的特征

T_(BB)DATA-REVEALED FEATURES OF ASIAN-AUSTRALIAN MONSOON SEASONAL TRANSITION AND ASIAN SUMMER MONSOON ESTABLISHMENT

采用日本气象研究所提供的ＴＢＢ资料分析了亚澳季风区的季节转换及亚洲夏季风建立的特征。发现４月份季节转换就已开始，５—６月是季节突变时期，６月份亚洲地区夏季风形势完全建立。冬季位于苏门答腊的对流中心由冬入夏沿着海洋大陆“大陆桥”和中印半岛系统地向北偏西移动，由此引起的大尺度环流改变导致了东南亚和印度地区夏季风的建立．而南海－百太平洋地区夏季风的建立则与中印半岛对流的活跃及副热带ＴＢＢ高值带（相应于西太平洋副高）的连续东撤紧密相关．

Based on TBB data from Meteorological Institute Research of Japan, a study is carried out of the features of seasonal transition of Asian-Australian monsoons and Asian summer monsoon establishment, indicaaing that the transition begins as early as April, followed by abrupt changes in May-June; the Asian summer monsoon sitUation is fully established in June. The winter convective center in Sumatra moved steadily northwestward across the 'iand btidge'of the maritime continent and the Indo-China Peninsula as time goes from winter to summer, thus giving rise to the change in large scale circulations that is responsible for the summer monsoon establishment over SE Asia and India; the South China Sea to the western Pacific summer monsoon onset hats a close relation to the active convection in the Indo-China Peninsula and the steady eastward retreat of the subtropical high-valued TBB band, corresponding to the western pacific subtropocal high.ac Tabs work is supported jointly by Chads State Meteoroledcal Adm￣ttation Monsoon ￣ration F￣ and the Natiffetural seenas Foundation of China.